<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>三角制作</title>
    <style>
        .box1 {
            width: 0;
            height: 0;
            /* border: 10px solid pink; */
            border-top: 10px solid pink;
            border-right: 10px solid red;
            border-bottom: 10px solid blue;
            border-left: 10px solid green;
        }
        
        .box2 {
            width: 0;
            height: 0;
            border: 50px solid transparent;
            border-left-color: pink;
            margin: 100px auto;
        }
        
        .jd {
            position: relative;
            width: 120px;
            height: 250px;
            background-color: #ffff00;
        }
        
        .jd span {
            position: absolute;
            left: 120px;
            top: 30px;
            width: 0;
            height: 0;
            border: 5px solid transparent;
            border-left-color: #00ff00;
        }
    </style>
</head>

<body>
    <div class="box1"></div>
    <div class="box2"></div>
    <div class="jd">
        <span>

        </span>
    </div>
</body>

</html>